640735950977 has 8 divisors (see below), whose sum is σ = 642409881960. Its totient is φ = 639063250560.

The previous prime is 640735950971. The next prime is 640735951001. The reversal of 640735950977 is 779059537046.

It can be written as a sum of positive squares in 4 ways, for example, as 1198267456 + 639537683521 = 34616^2 + 799711^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 640735950977 - 2⁸ = 640735950721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640735950971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 739733 + ... + 1352285.

It is an arithmetic number, because the mean of its divisors is an integer number (80301235245).

Almost surely, 2^640735950977 is an apocalyptic number.

It is an amenable number.

640735950977 is a deficient number, since it is larger than the sum of its proper divisors (1673930983).

640735950977 is a wasteful number, since it uses less digits than its factorization.

640735950977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 615283.

The product of its (nonzero) digits is 50009400, while the sum is 62.

The spelling of 640735950977 in words is "six hundred forty billion, seven hundred thirty-five million, nine hundred fifty thousand, nine hundred seventy-seven".